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310TAL IIOTITTCFLTURAL SOCIETY. 
analogy made known by Mr. Bates, which have lately formed the 
subject of discussion at the British Association and in the pages 
of ' Nature,' in which I observe with pleasure that one of our 
body, Mr. A. W. Bennett, has borne an honourable part. Neither 
he nor any of the gentlemen who have written on the subject, 
have, however, so far as has come under my notice, brought the 
point to its real issue. They have accepted battle on the field on 
which Mr. Bates has placed it; and although they may have 
achieved a victory over him, they have not succeeded in rescuing 
the subject from its obscurity. He may be wrong without their 
being right. I am not surprised at their having been led to accept 
his premises : when I first approached the subject I did the same ; 
but the longer I live and the more extended my experience be- 
comes, the more surely do I find that when a theory looks shaky 
and unsound, the place to look for the flaw is not in the upper 
story, but in the basement. It is in the foundation that the 
crack will almost invariably be found : I am sure it is so here. 
Mr. Bates found in the Valley of the Amazons a number of 
species of a northern tribe of butterflies wearing the colour and 
form of a Brazilian tribe, and so like in their varieties and strains 
that they obviously represent some different phenomenon from 
the ordinary one of mere diff'erence in species. To account for 
this he devises a theory on the Natural Selection plan. The 
Brazilian tribe has a bad smell, and birds and insects of prey 
consequently do not feed upon them ; and the northern tribe, in 
the course of their variation in the dark, accidentally produce 
one something like the Brazilian one, which produces others in 
the same direction by Natural Selection, until the mimics are 
brought to perfection. Every inch of the ground he goes over 
here is rained and unsound : the bad smell has not been observed 
in North America, where similar mimicry occurs ; birds and in- 
sects of prey hunt by sight and not by smell ; and the various 
communications on the subject in ' Nature ' point out a variety of 
other insuperable objections. But my object is not so much to 
show that a friend and entomological brother has been seduced 
by a " bad smell "to go on a wrong scent, like a good dog after 
a red herring, but to find out the true explanation of the pheno- 
menon. 
The explanation seems to me to be simply hybridization ; 
but before committing myself to it, as there were one or two 
points on which I was not sure how far the phenomena corre- 
